1. Field of the Invention
The present invention relates to novel organosilicon compounds, to a process for the preparation thereof, and to their applications in the field of nonlinear optics.
This invention especially relates to novel hyperpolarizable organosilicon compounds which are particularly active in nonlinear optics applications.
2. Description of the Prior Art
As reported by J. Zyss and I. Ledoux in the article in L'Echo des Recherches, 1st quarter, 1987, entitled "Organic molecules and the treatment of optical signals", the development of optical telecommunications requires the availability of components that include materials having strong nonlinear capabilities of the second or third order.
Numerous compounds, both organic and inorganic, are thus used in different forms, such as solutions, polymers, doped polymers, monomolecular layers, liquid crystals, single crystals, polymeric liquid crystals, and the like.
The organic compounds are especially interesting, as the synthesis of a wide variety of products is generally possible. Furthermore, most of the organic compounds have a great resistance to external effects (humidity, acidity, oxidation, etc.).
J. F. Nicoud and R. J. Twieg, in their paper entitled "Design and synthesis of organic compounds for efficient second harmonic generation" list different molecules which are active in the field of nonlinear optics.
These molecules have carbon chain skeletons generally comprising aromatic rings, substituted on the one hand by electron donating groups and, on the other, by electron accepting groups.
Thus, the dislocation and circulation of .pi. electrons and the non-centrosymmetry of the molecule generate a strong hyperpolarizability of the second and third order.
Large scale research efforts have to date been continuously carried out in an effort to develop novel compounds having nonlinear optical activity.